The Experts below are selected from a list of 282 Experts worldwide ranked by ideXlab platform

Etienne Brion - One of the best experts on this subject based on the ideXlab platform.

  • spontaneous emission of a sodium rydberg atom close to an optical nanofibre
    Journal of Physics B, 2019
    Co-Authors: E Stourm, Nic S Chormaic, Etienne Brion, Klaus Mølmer, Maxence Lepers, Romain Guérout, J Robert, Y Zhang
    Abstract:

    We report on numerical calculations of the spontaneous emission rate of a Rydberg-excited sodium atom in the vicinity of an optical nanobre. In particular, we study how this rate varies with the distance of the atom to the bre, the bre's radius, the symmetry s or p of the Rydberg state as well as its Principal Quantum Number. We nd that a fraction of the spontaneously emitted light can be captured and guided along the bre. This suggests that such a setup could be used for networking atomic ensembles, manipulated in a collective way due to the Rydberg blockade phenomenon.

Maxence Lepers - One of the best experts on this subject based on the ideXlab platform.

  • spontaneous emission of a sodium rydberg atom close to an optical nanofibre
    Journal of Physics B, 2019
    Co-Authors: E Stourm, Nic S Chormaic, Etienne Brion, Klaus Mølmer, Maxence Lepers, Romain Guérout, J Robert, Y Zhang
    Abstract:

    We report on numerical calculations of the spontaneous emission rate of a Rydberg-excited sodium atom in the vicinity of an optical nanobre. In particular, we study how this rate varies with the distance of the atom to the bre, the bre's radius, the symmetry s or p of the Rydberg state as well as its Principal Quantum Number. We nd that a fraction of the spontaneously emitted light can be captured and guided along the bre. This suggests that such a setup could be used for networking atomic ensembles, manipulated in a collective way due to the Rydberg blockade phenomenon.

Tilman Pfau - One of the best experts on this subject based on the ideXlab platform.

  • from molecular spectra to a density shift in dense rydberg gases
    Nature Communications, 2014
    Co-Authors: Anita Gaj, Jonathan B Balewski, Alexander T. Krupp, Robert Löw, Sebastian Hofferberth, Tilman Pfau
    Abstract:

    Ultracold Rydberg atoms — atoms with highly excited electrons — can form molecules with ground state atoms. By tuning the Principal Quantum Number of the Rydberg state, Gaj et al. study the transition from resolvable molecular lines to the mean shift regime, where indistinguishable lines form a band.

  • observation of ultralong range rydberg molecules
    Nature, 2009
    Co-Authors: Vera Bendkowsky, Bjorn Butscher, J Nipper, James P Shaffer, Tilman Pfau
    Abstract:

    In a Rydberg atom, at least one electron is excited into an orbital with a very high Principal Quantum Number that extends the atom's electronic envelope far beyond the nucleus. Based on ideas introduced by Enrico Fermi in 1934, a recent piece of theoretical work predicted that the scattering of such an electron from a second atom in the ground-state could give rise to attractive interactions. This would yield giant molecules with internuclear separations reaching several thousand Bohr radii. The spectroscopic characterization of such ultra-long-range 'Rydberg molecules' is now reported. The molecules, ultracold rubidium dimers, have spectra in good agreement with model predictions. This achievement raises the exciting prospect of realizing other exotic molecular species such as the so-called trilobite molecules in the near future. A Rydberg atom has one electron excited into an orbital with a very high Principal Quantum Number. The scattering of such an electron from a second atom in the ground state gives rise to long-range bonding, yielding giant molecules with internuclear separations reaching several thousand Bohr radii. Using s-state rubidium Rydberg atoms with Quantum Numbers between 34 and 40, Bendkowsky and colleagues have now spectroscopically characterized such 'Rydberg molecules', and measured their lifetimes and polarizabilities. Rydberg atoms have an electron in a state with a very high Principal Quantum Number, and as a result can exhibit unusually long-range interactions. One example is the bonding of two such atoms by multipole forces to form Rydberg–Rydberg molecules with very large internuclear distances1,2,3. Notably, bonding interactions can also arise from the low-energy scattering of a Rydberg electron with negative scattering length from a ground-state atom4,5. In this case, the scattering-induced attractive interaction binds the ground-state atom to the Rydberg atom at a well-localized position within the Rydberg electron wavefunction and thereby yields giant molecules that can have internuclear separations of several thousand Bohr radii6,7,8. Here we report the spectroscopic characterization of such exotic molecular states formed by rubidium Rydberg atoms that are in the spherically symmetric s state and have Principal Quantum Numbers, n, between 34 and 40. We find that the spectra of the vibrational ground state and of the first excited state of the Rydberg molecule, the rubidium dimer Rb(5s)–Rb(ns), agree well with simple model predictions. The data allow us to extract the s-wave scattering length for scattering between the Rydberg electron and the ground-state atom, Rb(5s), in the low-energy regime (kinetic energy, <100 meV), and to determine the lifetimes and the polarizabilities of the Rydberg molecules. Given our successful characterization of s-wave bound Rydberg states, we anticipate that p-wave bound states9, trimer states10 and bound states involving a Rydberg electron with large angular momentum—so-called trilobite molecules5—will also be realized and directly probed in the near future.

P C Kepple - One of the best experts on this subject based on the ideXlab platform.

  • stark broadening of high Principal Quantum Number hydrogen balmer lines in low density laboratory plasmas
    Physical Review E, 2007
    Co-Authors: E Stambulchik, Hans R. Griem, S Alexiou, P C Kepple
    Abstract:

    We present results for Stark broadening of high Principal Quantum Number (up to n=15) Balmer lines, using an analytical (the ''standard theory'') approach and two independently developed computer simulation methods. The line shapes are calculated for several sets of plasma parameters, applicable to radio-frequency discharge (N{sub e}{approx_equal}10{sup 13} cm{sup -3}) and magnetic fusion (N{sub e}{approx_equal}10{sup 15} cm{sup -3}) experiments. Comparisons of the calculated line profiles to the experimental data show a very good agreement. Density and temperature dependences of the linewidths, as well as relative contributions of different Stark-broadening mechanisms, are analyzed. It is seen that the standard theory of line broadening is sufficiently accurate for the entire set of plasma conditions and spectral transitions considered here, while an alternative theory (''advanced generalized theory'') is shown to be inadequate for the higher-density region. A discussion of possible reasons for this disagreement is given.

E Stourm - One of the best experts on this subject based on the ideXlab platform.

  • spontaneous emission of a sodium rydberg atom close to an optical nanofibre
    Journal of Physics B, 2019
    Co-Authors: E Stourm, Nic S Chormaic, Etienne Brion, Klaus Mølmer, Maxence Lepers, Romain Guérout, J Robert, Y Zhang
    Abstract:

    We report on numerical calculations of the spontaneous emission rate of a Rydberg-excited sodium atom in the vicinity of an optical nanobre. In particular, we study how this rate varies with the distance of the atom to the bre, the bre's radius, the symmetry s or p of the Rydberg state as well as its Principal Quantum Number. We nd that a fraction of the spontaneously emitted light can be captured and guided along the bre. This suggests that such a setup could be used for networking atomic ensembles, manipulated in a collective way due to the Rydberg blockade phenomenon.